This application claims the priority of Korean Patent Application No. 2003-53446, filed on Aug. 1, 2003, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a smart label and a manufacturing method thereof, and more particularly, to a smart label having a rolled antenna, and a method of manufacturing the same.
2. Description of the Related Art
A radio frequency identification (RFID) tag, typically known as a smart label, is an electronic tag to be attached to a variety of items in order to control or track inventory of the items in real time. Such a smart label incorporates a radio frequency identification technique developed to reduce certain disadvantages of the conventional product identification method using a barcode and a wired reader for reading the barcode information.
Utilizing the radio frequency identification method, product information stored in the smart label or RFID tag of a product can be effectively identified by a radio frequency transmitted from a terminal which is typically connected to a host for processing the information. The smart label consists generally of an IC chip and an antenna communicating with the terminal or reader. The smart label can be used in a wide variety of applications including inventory control, product managements, and automatic or computerized purchasing managements for store fronts. For example, smart labels can be attached to the stocked items of a warehouse for an automatic inventory control and production management. Korean Patent Application Publication No. 2004-15608 published on 19 Feb. 2004 and Korean Patent Publication No. 2004-35109 published on 29 Apr. 2004 disclose technologies relating to the smart label.
FIG. 1 is a plan view of a conventional smart label known in the art. Referring to FIG. 1, a smart label includes a semiconductor chip 13 mounted on an upper surface of a nonconductive substrate 11, and an antenna connected to and extending from an antenna port of the chip 21. The antenna 12 has a flat pattern which is typically formed in a loop or spiral shape. This antenna is typically formed by coating a conductive metal film on the surface of the substrate 11 and etching in the pattern. The antenna 12 includes an inner port 14 and an outer port 15 which are electrically connected to each other.
In manufacturing the conventional smart labels, the connection process of the inner port 14 and the outer port 15 of the antenna 12 has certain technical difficulties. For connecting the inner port 14 and the outer port 15, a part of the upper portion of the antenna 12 was insulated using an insulation member and the inner port 14 and the outer port 15 were connected using a conductive paste such as a silver (Ag) paste. However, since the silver paste coating method adopts a screen printing method, this connection process becomes complicated. Also, since the silver paste has a conductivity of limited value, a recognition distance of the RF antenna is also limited. If the width of a pattern is enlarged to enhance the conductivity, the overall size of the label increases.
As an alternative method known in the art, an insulation paste or an insulation tape was applied on the lower portion of the substrate and the inner and outer ports 14 and 15 were connected with a tape having a metal foil laminated thereon by an ultrasonic wave. Although this method enhances the recognition distance of the antenna, it causes an increase in manufacturing cost because of its complex process.